New research from the University of Bath and the University of São Paulo links childhood trauma to behavioural issues in teenagers that could elevate the risk of smoking, drug use, and poor diet, highlighting the importance of early intervention.
Childhood trauma may raise the odds that young people smoke, use drugs or develop unhealthy eating habits by fuelling behavioural problems in the teenage years, according to new research led by the University of Bath and the University of São Paulo. The study, published in the Journal of Child Psychology and Psychiatry, suggests that impulsivity, poor self-control and related conduct problems help explain how early adversity can shape later health risks.
The researchers analysed data from more than 4,000 participants in the 2004 Pelotas Birth Cohort in Brazil, one of the largest long-running studies of its kind. Unlike research that depends on adults remembering painful experiences years later, this project followed children over time, linking traumatic events in childhood with mental health in adolescence and health-related habits at age 18. That design, the authors said, gives a clearer view of how trauma may influence later behaviour.
The findings point most strongly to externalising problems, a term used for outwardly directed difficulties such as aggression, disruption and acting without thinking. These issues accounted for part of the connection between childhood trauma and smoking, illicit drug use, harmful alcohol use and diets high in ultra-processed foods. By contrast, internalising problems such as anxiety and depression appeared to play a much smaller role, which suggests that different kinds of mental health difficulties may affect later health in different ways.
Public health groups say that behaviour and conduct problems in children can be serious when they persist or interfere with daily life, and they stress that early treatment matters. The American Psychiatric Association describes disruptive, impulse-control and conduct disorders as conditions marked by difficulties managing aggression and impulses, while the Cleveland Clinic says these problems can begin in childhood and often require therapy and changes in parenting strategies. The Bath researchers argue that helping trauma-exposed teenagers regulate emotions and behaviour could therefore reduce both mental health difficulties and later physical health harm.
One striking finding was that these behavioural problems were also linked with higher levels of movement and physical activity. The authors said that raises the possibility of channeling restless or impulsive energy into structured activities such as team sports, which may offer healthier outlets. They now plan to examine whether childhood trauma is also tied to early signs of cardiometabolic disease in late adolescence, including higher resting heart rate, blood pressure, body weight and unhealthy blood fats. Although the study focused on young people in Brazil, the researchers say the implications are relevant far beyond that setting, where childhood adversity remains a significant public health concern.
Disclaimer: This content is for informational purposes only and is not intended to be a substitute for professional medical judgment, advice, diagnosis, or treatment.
